Valve offers more custom mod powerful than Warcraft 3 I think, however, the difficulty, time spent, especially the brokens. It left the custom mod much less variety than Warcraft 3 to the present day. I'll post here some custom mods that are abandoned but the developers have left the source-code of the custom mod for repair or continue, etc.
Island Troll Tribes 2
Ancient Wars
Island Troll Tribes 2
Ancient Wars